四级写作常见话题及范文：网络科技

　　Introduction

　　Internet, computer-based global information system. The Internet is composed of many interconnected computer networks. The Internet has made it possible for people all over the world to effectively and inexpensively communicate with one another. An individual who has Internet access can communicate directly with anyone else on the Internet, make information available to others, find information provided by others, or sell products with a minimum overhead cost.

　　The Internet has brought new opportunities to government, business, and education. Governments use the Internet for internal communication, distribution of information, and automated tax processing. In addition to offering goods and services online to customers, businesses use the Internet to interact with other businesses. Many individuals use the Internet for shopping, paying bills, and online banking. Educational institutions use the Internet for research and to deliver courses to students at remote sites.

　　The Internets success arises from its flexibility. Instead of restricting component networks to a particular manufacturer or particular type, Internet technology allows interconnection of any kind of computer network. No network is too large or too small, too fast or too slow to be interconnected.

　　An organization that has many computers usually owns and operates a private network, called an intranet, that connects all the computers within the organization. To provide Internet service, the organization connects its intranet to the Internet. Unlike public access networks, intranets are restricted to provide security. The restrictions allow computers inside the organization to exchange information but keep the information confidential and protected from outsiders.

　　Uses of The Internet（用途）

　　Companies, individuals, and institutions use the Internet in many ways. Companies use the Internet for electronic commerce, also called e-commerce, including advertising, selling, buying, distributing products, and providing customer service. In addition, companies use the Internet for business-to-business transactions, such as exchanging financial information and accessing complex databases. Businesses and institutions use the Internet for voice and video conferencing and other forms of communication that enable people to telecommute （work away from the office using a computer）.